Ammonoids are a diverse group of cephalopods, a group of molluscs that include squid, octopuses, cuttlefish and nautiloids. They lived for over 300 million years (from the Early Devonian – the end Cretaceous) and survived multiple mass extinctions. They finally succumbed to the mass extinction event at the end of the Cretaceous, the same event that killed the Dinosaurs. Ammonoid fossils are found abundantly around the world and offer palaeontologists a exceptional opportunity to study the evolution, life history and ecology of these fascinating invertebrates. Today we will be talking to Dr Kenneth De Baets from the Palaeontology Section, GeoZentrum Nordbayern about what we can learn about ammonoid ecology from the study of their fossils, and what this tells us about the evolution of living cephalopods.